1. Field of the Invention
The present invention relates generally to the fields of optical imaging and medical diagnosis. More specifically, the present invention relates to advanced methods of optical imaging of subsurface anatomical structures and biomolecules.
2. Description of the Related Art
The importance of imaging structures and biomolecules in humans is self-evident. Recently, many groups of investigators have been trying to develop optical imaging techniques in order to supercede, or reduce the requirements of using expensive and potentially harmful techniques including x-rays, ultrasound or magnetic and radio-frequency fields. Optical imaging techniques employing non-ionizing electromagnetic radiation are not harmful to biological tissue, and so are less hazardous and thus less expensive. However, there is a major limitation in using ultraviolet, visible and infrared radiant electromagnetic energy for imaging in that most tissues are highly scattering, and often strongly absorbing to such photons.
Nevertheless, infrared radiant energy is useful in non-invasive imaging of anatomical structures since it is relatively penetrating in tissue; the wavelengths of radiant energy from about 600 nm to about 1100 nm penetrates tissue quite well, when compared to visible, ultraviolet, or mid- to far infrared radiant energy. Furthermore, biomolecules exhibit absorption features in this red to near-infrared region of the spectrum due to electronic and vibrational/rotational absorption.
The prior art is deficient in the lack of effective means of imaging subsurface anatomical structures and biomolecules by using red and infrared radiant energy. The present invention fulfills this long-standing need and desire in the art.